Electromagnetic stepping switch



Dec. 24, 1963 M. TOMARO, JR

ELECTROMAGNETIC STEPPING SWITCH 3 Sheets-Sheet 1 Filed Oct. 2'7, 1961 7% #7 ATTORNEY Dec. 24, 1963 TOMARO, JR 3,115,563

ELECTROMAGNETIC STEPPING SWITCH 3 SheetsSheet 2 Filed Oct. 27, 1961 ATTORNEYS Dec. 24, 1963 p TOMARO, JR 3,115,563

ELECTROMAGNETIC STEPPING SWITCH Filed Oct. 27, 1961 3 Sheets-Sheet 3 lNVENTOR 2470/64 MEMW Q:

ATTORN EYS 'ljnited States Patent Ofiiice 3,115,563 Patented Dec. 24, 1963 3,]ll5563 ELEQTRQMAGNETTC dTEPPiNG SWllTClil Patricia vi. Tomaro, in, Mapiewood, NIL, assignor, by mesne assignments, to Walter E. Helier & Company, (inc), New York, NY, a corporation of Delaware Filed Oct. 27, 1961, Ser. No. 148,688 6 Claims. (Cl. ass res The present invention relates to electromagnetically operated switches in general and in particular to improvements in bidirectional sequence relays.

The invention finds particular utility in applications for the remote operation of television sets, hi-fi stereo and radio, lighting circuits ctc., wherein it is desired to sequentially switch an electrical function in the equipment at a distance remote from the apparatus. For instance, television sets usually have a channel selector switch having a plurality of rotary positions. In most prior art remote operations of such switches, it has been conventional to have a control relay having a single direction of rotation which thereby required the complete indexing through all the higher channels or switch posi tions in order to return to a lower numbered switch position. Obviously it is highly desirous to have a bidirectional type remotely controlled relay so that any desired switch or channel position may be selected without having to step through an unnecessarily high number of positions.

Accordingly, applicants invention provides a bi-directional sequence relay capable of being selectively impulsed to produce either a clockwise or counterclockwise sequential stepping through a plurality of switch positions.

Applicants invention, as embodied, employs two upstanding solenoid coils having plunger armatures each adapted when energized to index a gear or star wheel an incremental amount in either direction depending upon which solenoid coil is impulsed. The star wheel is adapted to carry a rotary wiper which electrically connects any one of the plural number of contacts arranged in a circular pattern to a common central contact. The invention is provided with an auxiliary switch, preferably of the snap-acting variety, which is adapted to operate at a predetermined angular position of the star wheel. The invention also includes a pair of adjustable taper pin stops to limit the angular position through which the star wheel and wiper may index. For this purpose a plurality of apertures are provided adjacent each of the contact points so that the pin stops may be readily inserted therein adjacent the desired contact/or contacts to thereby blank out the unwanted rotational portion of the sequence switch.

A feature of applicants rotary sequence relay is that it employs two linear acting solenoids to accomplish sequential switching. By employing linear solenoids increased pull-in power over a long range is obtained thereby insuring positive action of the switch for each impulse.

Accordingly, an object of the invention is to provide a rotary electromagnetic bi-directional sequence switch employing a pair of linear acting solenoids.

Another object of the invention is to provide a bidirectional relay having an easily adjustable angular stop/ or stops to vary the switching capacity to any desired number of positions.

Another object of the invention is to provide a sequence relay wherein the entire incremental indexing motion is determined by the pull-in stroke of the actuating solenoid.

Another object of the invention is to provide a novel reciprocal to rotary motion transfer mechanism capable of operating in either direction.

Another object of the invention is to provide a rotary sequence switch which operates reliably in any mounting plane.

A further object of the invention is to provide a relay operated switch which has a minimum number of parts, is simple and durable in construction, reliable in operation, extremely flexible in application, and economical to manufacture.

These and other objects and advantages of the inven tion will become apparent and the invention will be fully understood from the following description and drawings in which:

1G. l is an exploded perspective view of the invention showing the front contact plate hinged degrees from the rotary indexing star wheel;

FIG. 2 is a cross-sectional view with portions broken away taken along line 22 of FIG. 4 with parts broken away;

FIG. 3 is a horizontal cross-section of the invention taken along line 33 of FIG. 2;

FIG. 4 is a side elevation view, partially in section with portions broken away;

FIG. 5 is a sectional view taken along line 55 of FIG. 2 showing the snap-switch;

FIG. 6 is an enlarged section of the contact wiper arrangement; section on lines 66 of FIG. 3;

FIG. 7 is a cross-sectional view taken along line 77 of FIG. 4;

FIG. 8 is an enlarged view showing the operating relationship between the snap-switch and the recessed portion of the star wheel;

FIG. 9 is an enlarged view showing the action of the solenoid plunger arm upon the star wheel; and

FIG. 10 is a view similar to FIG. 9 showing the action f the plunger arm upon the star wheel for rotation of the wiper in th opposite direction of FIG. 9.

Referring to the drawings and in particular to FIGS. 1 and 4, a sequence relay shown generally at it) includes an actuator portion 12 and a contact portion 14. The actuator portion 12 includes a generally U-shaped frame member 16 enclosed by a cover plate 155, secured to the former through formed tabs 24). A pair of solenoid coils 21 each having windings 22 about a tubular bobbin 2d, are held in upright spaced relation within the frame 16 by the cover 15. The tubular bobbin 24 is provided with a vertically reciprocal plunger 26 made of any suitable magnetic material. The plunger 26 is provided at its lower end with a recessed conical portion at) to improve the magnetic coupling thereof with a similarly shaped conical head portion 44 of a rivet 42. An enlarged upper portion 28 of each of the plungers 26 secures a plastic stop washer member 3t and a transverse arm 32 thereto. Each of the arms 32 extends transversely to an overhanging position and is provided with a depending ear portion 3 i. Each of the plungers 26 is normally held in a raised position by a coil spring 3 secured at its lower end to a mid-portion of its respective arm 32 and at its upper end to an ear portion 37 of tie front face 48 of the frame 16. Each of the windings 22 is provided with suitable terminal portions 3-8 through which the desired operating current may be applied to energize the solenoid and thus lower the plunger 26 from their unenergized positions shown in PEG. 4.

The contact portion 12 of the sequence relay includes a fixed pivot pin id secured at one end as by riveting to the front face portion 48 of the frame 16. Extending also from the front face 43 are three projecting leg portions 5% which engage corresponding apertures 52 of a contact supporting insulation board 54. The board 54 is held against the actuator portion of the assembly by a 0 clip 56 which engages a corresponding annular groove at the free end of the pin 46. The insulating board 54 mounts a plurality of electrical terminals 62, each secured to the board by a rivet ea whose heads form the electrical contacts for the sequence switch. The terminals 62;, and rivet contacts at are arranged in a circular pattern about a central circular contact 64 which is secured to the insulating board 54. The contact portion 64 has a projecting terminal portion 66 extending through the insulating board 54.

Rotationally supported upon the pivot pin 4-6 is an index or star wheel 75 which may be made of any suitable insulating and self-lubricating type plastic such as nylon. The star wheel 73 includes a plurality of teeth 82} on the side thereof adjacent the actuator portion 12, while at the opposite side includes a smaller diameter cylindrical portion having a fiat surface 8t thereon. The latter side of the star wheel 73 carries a stop arm '76 and a wiper member 7% fitted over the flat 80 to be held thereto in fixed relation. The wiper member 70 includes a contact portion 72 and a resilient spring arm '74. An electrically conductive coil spring 63 is held in compression between the face of the contact 64 and the face of the wiper member 7% to complete the electrical circuit from the terminal 66 through the wiper arm contact 72 to the selected rivet head no and terminal 62 depending upon the rotational position of the star wheel 78.

The star wheel '78 includes a peripheral depression or recess 84 for operating a snap switch assembly shown generally at as. The switch assembly includes a pair of electrical terminals 83 secured by rivets to an insulated base portion 9%. A switch control arm 92 is pivotally supported in a slot 94 of upstanding member 95. One end of the control arm 92 carries a follower head 1th) in alignment with the portion of the star wheel 78 carrying the depression 84-. The opposite end of the switch control arm 92 en ages one end of a leaf spring 96 of the snap switch so that upon downward motion of the follower lit a corresponding upward movement of the left end of the leaf spring )6 occurs (see FIG. 2). As the follower 1% travels downward the plane of the leaf spring 96 raises to a point where it coincides or is above the base point N2 of the upwardly arched spring portion lit)? of the spring 96 so that the contact 98 at the other end of the leaf spring will transfer abruptly to a raised position to make electrical contact with the underside of member 163 and thereby complete the electrical circuit between terminals 8S8S at the zero angular position of the star wheel.

As best seen in FIG. 1 the insulating board 54 is provided with a plurality of circularly spaced apertures 1%, adjacent each of the contacts 60. Engageable with selected apertures 1% are a pair of tapered stop pins 1% which may be readily inserted therein. The inner end of each of the stop pins 1%, when inserted, extends sulticienny inward to overlie the circular path transcribed by the rotation of the stop arm it carried by the star wheel immediately behind the wiper arm assembly 70, to thereby limit the angular freedom through which the star wheel may be impulsed. Obviously, if the applica tion is such that continuous rotation of the switch is desired, the stop pin need not be employed. However, those skilled in the art will readily recognize that some switch applications will require less switching positions than the capacity of the switch affords and accordingly the unwanted positions may be readily blocked off by the insertion of a pair of stop pins to reduce the angular freedom of the wiper 7d. In other applications it may be desirable to insert but a single stop pin or none at all.

In the operation of applicants novel sequence relay, the desired electrical connections would be made to the common terminal 66 and the individual terminals 62. The terminals 83-88 of the snap switch assembly 86 could be wired with a separate electrical circuit. Upon energization of the left hand solenoid coil, through its terminals 38, a downward movement of its plunger 26 and associated arm 32 would occur (see FIG. 9) transferring the ear portion 34; from the dotted position to its lowermost energized position as shown in full lines. As the ear portion 3d descends vertically downward, initial contact is made with the horizontal surface of the tooth 82 immediately therebelow. Upon continued downward movement of the ear 34 against the tooth 82, which imparts a counterclockwise rotation to the star wheel, the entire plunger 26 and arm 32 assembly is free to rotate to the left to the position shown in full lines. Accordingly, as will be readily apparent from an inspection of the operation in the clockwise and counterclockwise direction as shown in FIGS. 10 and 9 respectively, as each of the solenoids is alternately energized a reciprocating as well as limited angular rotation is imparted to the solenoid plunger during its energization stroke. Upon deenergization the obliquely oriented coil springs 35-36 function to raise the solenoid armature to its uppermost position as well as angularly return it to a position vertically above the next adjacent star wheel tooth. With this arrangement applicants novel design is capable of translating a limited reciprocal motion of either of the plungers into an incremental rotary motion to the star wheel, without recourse to a complex ratchet and pawl device. All of the angular rotation imparted to the star wheel '78 occurs during the energization stroke of the solenoid plunger. The springs 36 serve merely to return the ear portions 34-34 of their respective armature to a proper initial position in readiness for subsequent energization.

Thus it can be seen how the invention has provided a bi-directional sequence relay capable of easy adaptation to any desired mode of operation either for unlimited rotary motion or any desired limited angular amount of freedom by the mere adjustment of one or more stop pins. Furthermore, because of the dual reciprocating solenoids, strong positive indexing is assured upon each energization thereof. The design employs a minimum of parts all of which are easy and economical to manufacture.

While a specific embodiment of the invention has been shown and described in detail to illustrate the application of the inventive principles, it will be understood that the invention may be embodied otherwise without departing from such principles.

What is claimed is:

1. A rotary bi-directional electromagnetic switch comprising, a frame, a first solenoid coil, a second solenoid coil, said coils being mounted in spaced parallel relation upon said frame, plunger means associated with each of said coils normally held in one position and axially and rotationally movable to another position upon energization of said coils, a member having a central electrical contact thereon, a plurality of electrically insulated contacts secured to said member circularly arranged about said central contact, a star wheel having a plurality of teeth about the periphery thereof, means pivotally mounting said star wheel about an axis of rotation between, and perpendicular to, the lines of action of said plunger means, conductive wiper means carried by said star wheel to electrically connect a selected one of said plurality of contacts to said central contact, stop means projecting through said member to limit the pivotal freedom of said star wheel, and arm means connecting each of said plunger means to said star wheel whereby energization of said first or second solenoid coils will efiect incremental clockwise or counterclockwise rotation of said star wheel, each of said arm means including a pawl portion overlying a tooth on opposite sides of said star wheel, said pawl portion being effective when operated by energization of its respective solenoid coil to contact a first tooth of said star wheel to rotate the star wheel and to be contacted by a second following tooth of said star wheel to rotate said pawl portion and arm means about the line of action of its respective plunger means.

2. A rotary bi-directional electromagnetic switch comprising, a frame, a first solenoid coil, a second solenoid coil, said coils being mounted in spaced parallel relation upon said frame, plunger means associated with each of said coils normally held in one position and axially and rotationally movable to another position upon energization of said coils, a member having a central electrical contact thereon, a plurality of electrically insulated contacts secured to said member circularly arranged about said central contact, a star wheel having a plurality of teeth about the periphery thereof, means pivotally mounting said star wheel about an axis of rotation between, and perpendicular to, the lines of action of said plunger means, conductive wiper means carried by said star wheel to electrically connect a selected one of said plurality of contacts to said central contact, a pair of adjustable stop means extending through said member to engage and establish predetermined clockwise and counterclockwise angular limits of rotation of said star wheel, and arm means connecting each of said plunger means to said star wheel whereby energization of said first or second solenoid coils will effect incremental clockwise or counterclockwise rotation of said star wheel, each of said arm means including a pawl portion overlying a tooth on opposite sides of said star wheel, said pawl portion being effective when operated by energization of its respective solenoid coil to contact a first tooth on said star wheel to rotate the star wheel and to be contacted by a second following tooth of said star wheel to rotate said pawl portion and arm means about the line of action of its respective plunger means.

3. A rotary switch including an electrical solenoid having a reciprocating armature, a ratchet wheel having peripheral teeth and mounted for pivotal rotation about an axis at right angles to the line of movement of said armature, arm means attached to the said armature and extending outwardly at substantially right angles to the line of action thereof and substantially parallel to the ratchet wheel axis of rotation, said arm means including an integral pawl portion for engaging the teeth on the periphery of the ratchet wheel, said arm means being free to rotate about the line of action of the armature during energization of said solenoid as the pawl portion contacts a selected tooth of the ratchet wheel and is abutted by a second following tooth of the ratchet wheel, and spring means for axially and rotationally returning the pawl portion and arm means to an unenergized position in line with the next following tooth on the periphery of said ratchet wheel.

4. A rotary bi-directional electromagnetic switch comprising a frame, a first solenoid coil, a second solenoid coil, said coils being mounted in spaced parallel relation upon said frame, plunger means associated with each of said coils normally held in a first position and axially movable to another position upon energization of said coils, a member having a central electrical contact thereon, a plurality of electrically insulated contacts secured to said member circularly arranged about said central electrical contact, a star wheel having a plurality of teeth about the periphery thereof, means pivotally mounting said star wheel about an axis of rotation between and perpendicular to the lines of action of said plunger means, conductive wiper means carried by said star wheel to electrically connect a selected one of said plurality of contacts to said central electrical contact, arm means connecting each of said plunger means to said star wheel, each of said arm means including a pawl portion overlying a tooth on opposite sides of star wheel, said pawl portion adapted when operated by energization of its respective solenoid coil to contact a first tooth of said star wheel to rotate the star wheel and to be contacted by a second following tooth of said star wheel to rotate said pawl portion and arm means about the line of action of its respective plunger means, and spring means to rotationally and axially return said pawl portion to its original position upon the de-energization of its respective solenoid coil.

5. A switch according to claim 4 wherein said member includes a plurality of circularly arranged openings therethrough adjacent the circularly arranged contacts thereon, and pin means extending through at least one of said openings for engaging a portion of said star wheel to thereby establish predetermined clockwise and counterclockwise angular limits of rotation thereof.

6. A switch according to claim 4 wherein each arm means extends transversely through an opening in said frame, an edge of said opening serving to abut said arm means and to thereby establish a predetermined limit of angular freedom of said pawl portion and arm means about the line of action of its respective plunger means upon energization of its associated solenoid coil whereby rotational overtravel of the star wheel is prevented.

References Qited in the file of this patent UNITED STATES PATENTS 1,504,227 Gent Aug. 12, 1924 2,046,143 Wyant June 30, 1936 2,093,074 Dickinson Sept. 14, 1937 2,433,805 Wolfi Dec. 30, 1947 2,452,747 Gomez Nov. 2, 1948 2,662,987 Johnson Dec. 15, 1953 2,762,952 Brunderlin Sept. 11, 1956 2,791,146 Kunz May 17, 1957 2,838,623 Wendling June 10, 1958 2,914,687 MacDonald Nov. 24, 1959 2,927,225 Phillips Mar. 1, 1960 2,928,916 Bonanno Mar. 15, 1960 FOREIGN PATENTS 809,512 Great Britain Feb. 23, 1959 

3. A ROTARY SWITCH INCLUDING AN ELECTRICAL SOLENOID HAVING A RECIPROCATING ARMATURE, A RATCHET WHEEL HAVING PERIPHERAL TEETH AND MOUNTED FOR PIVOTAL ROTATION ABOUT AN AXIS AT RIGHT ANGLES TO THE LINE OF MOVEMENT OF SAID ARMATURE, ARM MEANS ATTACHED TO THE SAID ARMATURE AND EXTENDING OUTWARDLY AT SUBSTANTIALLY RIGHT ANGLES TO THE LINE OF ACTION THEREOF AND SUBSTANTIALLY PARALLEL TO THE RATCHET WHEEL AXIS OF ROTATION, SAID ARM MEANS INCLUDING AN INTEGRAL PAWL PORTION FOR ENGAGING THE TEETH ON THE PERIPHERY OF THE RATCHET WHEEL, SAID ARM MEANS BEING FREE TO ROTATE ABOUT THE LINE OF ACTION OF THE ARMATURE DURING ENERGIZATION OF SAID SOLENOID AS THE PAWL PORTION CONTACTS A SELECTED TOOTH OF THE RATCHET WHEEL AND IS ABUTTED BY A SECOND FOLLOWING TOOTH OF THE RATCHET WHEEL, AND SPRING MEANS FOR AXIALLY AND ROTATIONALLY RETURNING 